Browsing by Author "Garrido, Jose Matias"
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- Item(-)-Epicatechin Solubility in Aqueous Mixtures of Eutectic Solvents and Their Constituents(2024) Bastias-Barra, Arturo I.; Gajardo-Parra, Nicolas F.; Cea-Klapp, Esteban; Arroyo-Avirama, Andres F.; Garrido, Jose Matias; Held, Christoph; Perez-Correa, Jose R.; Canales, Roberto I.(-)-Epicatechin is a polyphenol present in diverse natural sources. It shows positive human health effects, which makes it interesting for the pharmaceutical and food industries. Conventional solvents used for polyphenol extraction are mostly toxic and flammable, leaving unwanted impurities in the final product. Thus, solubility of (-)-epicatechin at 101.3 kPa and 293.15, 303.15, and 313.15 K was experimentally measured in water and binary systems composed of 25 wt % of water + 1,3-propanediol (13PD), glycerol (Gly), and two deep eutectic solvents based on choline chloride as hydrogen-bond acceptor and the previous polyols as hydrogen-bond donors (DES1 and DES2). Solubility results in water were obtained using spectrophotometric and gravimetric methodologies. Overall, (-)-epicatechin solubility varies widely among the studied solvents but only slightly within the experimental temperature range. Solvents in ascending order according to (-)-epicatechin solubility are water < Gly + water < 13PD + water < DES2 + water < DES1 + water. The solubility of (-)-epicatechin is significantly enhanced by introducing choline chloride into the investigated hydrogen-bond donors (HBDs) at a molar ratio of 1:3, accompanied by 25 wt % water. Perturbed-chain statistical associating fluid theory (PC-SAFT) solubility calculations were in quantitative agreement with experimental data.
- ItemHydrogen bond donor and alcohol chain length effect on the physicochemical properties of choline chloride based deep eutectic solvents mixed with alcohols(2022) Cotroneo-Figueroa, Vincenzo P.; Gajardo-Parra, Nicolas F.; Lopez-Porfiri, Pablo; Leiva, Angel; Gonzalez-Miquel, Maria; Garrido, Jose Matias; Canales, Roberto, IDeep eutectic solvents are mixtures typically composed by a hydrogen bond donor and a hydrogen bond acceptor. They have appeared as an alternative of ionic liquids in several processes due to their tunability, biodegradability and low cost. Recently, deep eutectic solvents have been studied as potential solvents for different applications. Then, their physicochemical properties need to be characterized for understanding the interaction between its constituents and with other compounds. Deep eutectic solvents prepared for this work are based on choline chloride mixed with ethylene glycol, 1,3-propanediol or 1,4-butanediol at a 1:3 mol ratio. FT-IR spectra was obtained for comparing the different structures of those deep eutectic solvents. Density and viscosity of the prepared deep eutectic solvents were measured from 293.15 K to 333.15 K at 101.13 kPa. Also, the same properties at the same temperature and pressure conditions were obtained for the mixtures of the three deep eutectic solvents with four alcohols: methanol, ethanol, 1-propanol or 1-butanol. Physicochemical (i.e density and excess volume) and transport properties (i.e viscosity) were measured and predicted using PC-SAFT and Free Volume Theory, respectively, for understanding the effect of the temperature variation, the length of the alcohol chain, and length of the hydrogen bond donor on the configurational aspects of the mixture. Subsequently, a prediction of the excess molar enthalpy was performed with COSMO-RS in order to assess the behavior of the same variables on different type of intermolecular interactions from the energetic point of view. The results suggest that mixing each deep eutectic solvent with an alcohol produce negative molar excess volumes and molar excess enthalpies, observing a higher affinity between unlike species. (C) 2021 Elsevier B.V. All rights reserved.
- ItemImpact of deep eutectic solvents and their constituents on the aqueous solubility of phloroglucinol dihydrate(2021) Gajardo-Parra, Nicolas F.; Do, Hoang T.; Yang, Mengyi; Perez Correa, Jose Ricardo; Garrido, Jose Matias; Sadowski, Gabriele; Held, Christoph; Canales, Roberto, I